PCI-E Video Card Power Problem - Techist - Tech Forum

Go Back   Techist - Tech Forum > Computer Hardware > Hardware Repairs and Troubleshooting
Click Here to Login
Thread Tools Display Modes
Old 08-07-2012, 04:25 PM   #1 (permalink)
Newb Techie
Join Date: Aug 2012
Posts: 2
Default PCI-E Video Card Power Problem

I have a Geforce 8800GT that was a part of my old setup. I had then replaced it with a Geforce 480. I was then running the Geforce 480 on the top PCI-E slot and the Geforce 8800 on the bottom slot. It was running fine for a while but then I started noticing like a burning or melting plastic smell coming from the computer. At first I had thought that it was the new power supply giving out but it turned out to be the Geforce 8800 that was getting heated up by the 480's heatsync. Eventually, the computer would keep crashing due to the 8800 overheating. I then pulled the 8800 out of my computer and have been running the 480 ever since. I had to do this not only due to the smell but the increasingly unstable 8800.

Now, I have reseated the heatsync on the 8800 and it seems to be fine. However the computer does not power on at all when the card is plugged into PCI-E power. The card can be in the PCI-E slot with no additional PCI-E power connected and the computer boots (but the card does not work obviously). As soon as one or both PCI-E power connectors are plugged into the card, the lights on the mobo flash for a fraction of a second when the power button is pressed and then the PSU goes back into stand-by. Subsequent attempts to press the power button do nothing until the capacitors in the PSU are cycled (power off for 30 seconds and then back on). Also, the same thing happens even if the card is not in the PCIE slot. So the card can be sitting outside of the PC and as soon as either or both PCI-E power connectors are connected to the card, the same problem occurs. It seems as though the PSU is entering a safety mode and preventing powerup.

Now I have inspected the card for damage to the power circuit. It all seems fine except for a small line (could be a crack??) in one of the transistors. I have a hard time believing however that this bad transistor would be detected by the PSU and block startup...

I'm just looking for opinions here on whether it's worth trying to replace the transistor on the card or if it's simply done for.

In short: Power Supply does not power on when video card is plugged in. Not a wattage issue. Unrelated to the motherboard.

I am running a 1000W PSU. I want the 8800GT back in there to power two extra LCD displays.

Thanks and sorry for the long post.

txlzone is offline   Reply With Quote
Old 08-07-2012, 05:40 PM   #2 (permalink)
patonb's Avatar
Join Date: Jan 2005
Location: In Gov't Regulated Cubical
Posts: 9,745
Default Re: PCI-E Video Card Power Problem

Wel;come to the forum.

I think you may need to try a buddys card in there to be sure. It's possible the heat cracked traces, the solder lines, or damaged the caps. This could be shorting out and poping the psu

Foldie = i5 6600kMSI Z170A M5 EVGA 970 SC Corsair H100 Corsair hx520 2x8gb GSkill Corsair 650D
Woohoo = L5639 @3.1Ghz EVGA SR-2 gtx 260-216 Hyper 212+ Corsair 1050hx 6x2gb Corsair XMS3 Blackhawk Ulra
Alienware 18 - SLI 770M 4700mq 16Gig

patonb is offline   Reply With Quote
Old 08-07-2012, 07:02 PM   #3 (permalink)
Newb Techie
Join Date: Aug 2012
Posts: 2
Default Re: PCI-E Video Card Power Problem

Thanks. Couldn't Google my problem so I decided to try out these forums

Yes, the computer works fine with my Geforce 480 which has a much higher wattage and runs a lot hotter (idle: 80 idle. 106 in furmark). I believe that it's this 106 degree heat right next to the 8800 that made it break. The shorting is my initial diagnosis as well as I believe it to be the only way it would prevent the PSU from powering up. The caps look fine, there's just that one transistor/voltage regulator that seems to have a tiny hairline crack in it. I will be taking a closer look at the card tonight and comparing it with the stock 8800 design. From there, I might either replace some of the components on the card or try freezing/baking it back into shape. Stay tuned.
txlzone is offline   Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
PCI cards (Video card + Video Card) not being recognized after fresh install of XP GMEN316 Microsoft Windows and Software 5 12-05-2008 09:04 PM
Conflict between PCI Video card and PCI Wireless Network Adapter otaku_mike Hardware Repairs and Troubleshooting 1 06-13-2007 12:01 PM
Can a power surge fry a PCI card? sprtnbsblplya New Systems | Building and Buying 6 06-07-2006 12:30 PM
Equal Yoke: fast AGP video card with slow PCI video, and performance markvolz Monitors, Printers and Peripherals 3 05-05-2006 10:07 AM
Best PCI Video Card Out There (NOT PCI-E) ManuelJ System Upgrades 6 10-08-2005 09:07 PM

Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -5. The time now is 08:35 PM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, vBulletin Solutions, Inc.